There is a need for reliable security in many places, including homes and offices. One of the most significant components of this security are door locks. Existing door lock systems which provide enhanced security to existing door latches and locks, and/or provide a system for remote control, have drawbacks which significantly affect their utility. In this regard, existing door lock systems are often designed in a manner which is incompatible with existing door latch and lock hardware, or requires significant modification to existing door latches and locks and/or the region surrounding the existing door latches and locks. Other drawbacks are the difficulties and complexities encountered to install prior art door lock systems. The present invention addresses these and other drawbacks to provide a remote door entry system which is versatile, convenient to use and install, and which is adapted for use in connection with existing door latch and door lock hardware.